From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Lee, Chun-Yi" Subject: [PATCH 1/2 v2] acpi: video: add function to support unregister backlight interface Date: Mon, 13 May 2013 15:43:56 +0800 Message-ID: <1368431037-21105-1-git-send-email-jlee@suse.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: mjg@redhat.com, rjw@sisk.pl Cc: platform-driver-x86@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, "Lee, Chun-Yi" , Carlos Corbacho , Dmitry Torokhov , Corentin Chary , Aaron Lu , Thomas Renninger List-Id: linux-acpi@vger.kernel.org There have some situation we unregister whole acpi/video driver by downstream driver just want to remove backlight control interface of acpi/video. It caues we lost other functions of acpi/video, e.g. transfer acpi event to input event. So, this patch add a new function, find_video_unregister_backlight, it provide the interface let downstream driver can tell acpi/video to unregister backlight interface of all acpi video devices. Then we can keep functions of acpi/video but only remove backlight support. Reference: bko#35622 https://bugzilla.kernel.org/show_bug.cgi?id=35622 v2: Also unregister cooling devices. Tested-by: Andrzej Krentosz Cc: Carlos Corbacho Cc: Matthew Garrett Cc: Dmitry Torokhov Cc: Corentin Chary Cc: Rafael J. Wysocki Cc: Aaron Lu Cc: Thomas Renninger Signed-off-by: Lee, Chun-Yi --- drivers/acpi/video.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/acpi/video.h | 2 + 2 files changed, 56 insertions(+), 0 deletions(-) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index c3932d0..f21104d 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -1861,6 +1861,60 @@ static int __init intel_opregion_present(void) return opregion; } +static acpi_status +find_video_unregister_backlight(acpi_handle handle, u32 lvl, void *context, + void **rv) +{ + struct acpi_device *acpi_dev; + struct acpi_video_bus *video; + struct acpi_video_device *dev, *next; + + if (acpi_bus_get_device(handle, &acpi_dev)) + return AE_OK; + + if (!acpi_match_device_ids(acpi_dev, video_device_ids)) { + video = acpi_driver_data(acpi_dev); + acpi_video_bus_stop_devices(video); + mutex_lock(&video->device_list_lock); + list_for_each_entry_safe(dev, next, &video->video_device_list, + entry) { + if (dev->backlight) { + backlight_device_unregister(dev->backlight); + dev->backlight = NULL; + kfree(dev->brightness->levels); + kfree(dev->brightness); + } + if (dev->cooling_dev) { + sysfs_remove_link(&dev->dev->dev.kobj, + "thermal_cooling"); + sysfs_remove_link(&dev->cooling_dev->device.kobj, + "device"); + thermal_cooling_device_unregister(dev->cooling_dev); + dev->cooling_dev = NULL; + } + } + mutex_unlock(&video->device_list_lock); + acpi_video_bus_start_devices(video); + } + return AE_OK; +} + +void acpi_video_backlight_unregister(void) +{ + if (!register_count) { + /* + * If the acpi video bus is already unloaded, don't + * unregister backlight of devices and return directly. + */ + return; + } + acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + ACPI_UINT32_MAX, find_video_unregister_backlight, + NULL, NULL, NULL); + return; +} +EXPORT_SYMBOL(acpi_video_backlight_unregister); + int acpi_video_register(void) { int result = 0; diff --git a/include/acpi/video.h b/include/acpi/video.h index 61109f2..1e810a1 100644 --- a/include/acpi/video.h +++ b/include/acpi/video.h @@ -19,11 +19,13 @@ struct acpi_device; #if (defined CONFIG_ACPI_VIDEO || defined CONFIG_ACPI_VIDEO_MODULE) extern int acpi_video_register(void); extern void acpi_video_unregister(void); +extern void acpi_video_backlight_unregister(void); extern int acpi_video_get_edid(struct acpi_device *device, int type, int device_id, void **edid); #else static inline int acpi_video_register(void) { return 0; } static inline void acpi_video_unregister(void) { return; } +static inline void acpi_video_backlight_unregister(void) { return; } static inline int acpi_video_get_edid(struct acpi_device *device, int type, int device_id, void **edid) { -- 1.6.4.2